• Response of seedling community to season and topography in mid mountain moist evergreen broad leaved forest in the Ailao shan , Yunnan

    Subjects: Biology >> Botany >> Applied botany submitted time 2024-05-07 Cooperative journals: 《广西植物》

    Abstract: Seedling is the most important stage during the life history of plant and plays a critical role in the forest regeneration. We studied the species composition seasonal dynamics and spatial distribution of tree seedlings in the 20 hm 2 Ailaosha n forest dynamics plot . The forest dynamics plot was built in a mid mountain moist evergreen broad leaved forest in the Ailaoshan. Within the 20 hm 2 plot, we established 450 seedling quadrats of size 1 m × 1 m . We investigated the species composition, seas onal recruitment, seasonal mortality and spatial distribution of tree seedlings for four years ( from 2019 to 2022). The results were as follows: 1 We recorded a total of 2 928 seedlings of 58 species belonging to 42 genera and 26 families. There were 817 recruits of 47 species and 1 181 dead seedlings of 50 species. (2) The i mportance val u e s of tree seedlings varied among different tree species across years . Symplocos ramosissima and Machilus bombycina were t he dominant species, with importan ce values con sistently in the top 2 in four years while the importan ce value of the pioneer species Viburnum cyclindricum decline d continuously (3) W e didn't find significant differences in species richness, average species richness in a quadrat, species diversity S hannon Wiener index, Simpson index) index), abundance, recruits, recruitment rate, mortality and mortality rate of tree seedlings between different seasons. 4 The majority of species exhibited restricted distribution within the plot, wh ile only a few species di splayed a broader distribution across the plot. Topography was found to determine the distribution and diversity of tree seedlings with higher species richness, density and diversity (Shannon Wiener index and Simpson index) in the flat topography compared to the ridge and valley of the plot . T hese findings suggest that we don't find significant differences in community composition, recruitment and mortality of tree seedlings between different seasons. Topography influences the spatial distribution and diver sity of tree seedlings. The present study reveals the dynamics of recruitment and mortality of tree seedlings and provide the theoretical basis for biodiversity conservation and forest management.